There have been a number of tragic deaths in which children have been mistakenly left in automobiles after the driver had reached their desired destination and left the vehicle. The deaths have usually been caused by a buildup of excessive heat or excessive cold within the vehicle during the absence of the driver. Infants, in particular, are susceptible to dehydration when subjected to the elevated temperatures within an enclosed vehicle, and can easily slip into a comatose state.
One system for preventing children from becoming inadvertently locked within a vehicle is described in U.S. Pat. No. 5,793,291. The system utilizes a motion detector to detect the presence of a child or pet within a located vehicle. While this system provides some advantages, particularly in the case of older children that may inadvertently lock themselves in a vehicle while playing and may be actively seeking escape, it fails to protect infants who have been left asleep in their child seats and are not capable of sufficient activity to set off a motion detector. Infants, for example, may become dehydrated during sleep and may drift into a comatose state without ever waking.
In view of the above, it is an objective of the invention to provide a system that warns when a child has been left in the infant seat under dangerous conditions. It is a further object of the invention to provide a system that warns when a child has been left in an infant seat and the vehicle's ignition has been turned off.